In the separation of a gaseous or liquid medium from solid particles or in the classification of particles by size, there is a need for a relatively simple and efficient apparatus. For example, in the combustion of carbonaceous material containing sulfur and ash, such as coal, the gases of combustion may contain sulfur compounds representing a major portion of the sulfur found in the material, as well as ash particulates. Since sulfur compounds and particulates may constitute significant environmental hazards, much work has been devoted to the development of methods for preventing formation of these substances or cleansing them from the combustion gases.
Several patents which teach cyclone burners as well as processes for burning fuel to reduce emissions include U.S. Pat. Nos. 4,101,412; 4,232,615; 4,257,760; and 4,542,704. However, such equipment is not as efficient as the present cyclone separator which can reduce the percent of ash which is emitted from the separator along with the hot combustible gas. In addition, there is a need for a separator which can separate solid particles from a high temperature gas stream by elutriation. Such a device could find application above a fluid bed combustor or in fluid bed reaction systems.
Now a cyclone separator has been invented which requires the recoverable product to make a radius turn before leaving the separator. This required turn increases the centrifugal force acting on the solid particles and assists in separating them from the recoverable product.